Over the course of nearly two hours (much of which I could hear but not see from my perch in San Francisco) British scientist Stephen Wolfram showed off the system, described what was happening and answered questions on the project.

It appeared that he stayed pretty much on a script of the sorts of data that he put into the search engine - this was not a fully open demo by any stretch of the imagination - although on a couple of occasions he did use search queries from the audience, but they were not generally successful.

• It is a web search engine, but it's a search engine that is on the web, not an engine that searches the web. It's essentially a front end to a enormous, interlinked database of verified - usually academic - information. Putting in terms throws back charts, graphs and other answers around the subject you're quizzing it about. (no surprise that Google's decided that now is a good time to show off its new charts display)

• There's a lot of data drawn from the hard sciences, engineering and so on. There's a lot from Mathematica, the computational software Wolfram also makes. Not so much input from pop culture or the day to day world of fleeting information and consumption. To get an idea of what the system knows, Wolfram claims that "probably 90% of the shelves in a reference library we can say we've got a reasonable start on".

• It's a bit like a semantic web application, but the ontologies and structures are peculiar. "If the semantic web had been a 100%, overwhelming thing in the world, our job would have been a lot easier," he said, adding that at some point he hopes to "expose some of our data depository mechanism" to the public.

• The business model is fairly familiar. There will be a free, online front end that can be accessed by anyone. The site will have messages from what Wolfram called "corporate sponsors" (in other words, display adverts) and these will be supplemented in the future by "vendor-provided information" (targeted adverts). There will also be a paid-for, pro version for people who want to use the system to interrogate their own data.

• It's not really doing any natural language processing - that is, in Wolfram's words, the engine actually gets rid of "pure linguistic fluffery" and really just understands keywords and operators. He expects people to quickly stop using natural language and start using the relevant jargon.

The Q&A session focused on a series of very similar questions - how do you judge the veracity of sources? How fresh are they? What happens if Wolfram Alpha doesn't know the answer? Can people input their own data? What about proprietary information?

These were all answered at length, despite being fairly straightforward: in general, for non-paying users, the system's owners find and curate data, which they give weight according to their own judgment. If the system doesn't know the answer to something, it reverts to a more traditional web search engine system where it points you towards places that might have the information you're looking for.

I'm left relatively impressed, and can see myself using it a fair bit for fact-checking purposes or various calculations. But I want to see more: is this a useful tool for ordinary people, or a souped-up scientific calculator? I've asked a couple of times now for access to the beta, but they appear to be dribbling it out in seemingly random ways.

Have you got access to it? Or did you seen the webcast and form an opinion?